Supermoves in Freecell-like games

How do you know how many cards you can move in FreeCell?

Freecell solitaire and some other solitaire games allow to move only one card from one tableau pile to another. But, as a shortcut, BVS Solitaire Collection will allow you to move a full or partial build if there are enough empty tableau piles and empty cells, because you would have been able to get the same result by temporarily moving the extra cards into these empty spaces.

This is commonly called a supermove in FreeCell terminology. It allows you to take full advantage of empty cells and tableau piles and saves a lot of time. The maximum number of cards that can be "supermoved" is (c+1)*2^t if there are c empty cells and t empty tableau piles. If the destination pile of the supermove is the empty tableau pile, this tableau pile is not counted in the formula.

If there are no cells in the game, this formula just looks as 2^t, where t is the number of empty tableau piles.